EGR valve emission question

[dually-dump]

I keep getting referenced to an EGR valve that only has one flange. Mine has two flanges. Does anybody have a source for an 11/81 (1982?) sd22 vin# JN6SD02S2.....egr valve. Is this really my problem if I have low power and bad fuel mileage? Also, where are the marks for finding TDC when adjusting the valves? I am new here. I have an 82' 720 pickup sd22 engine. It has a dump bed w/duallys that appears to have been put on in LA, fresh off he boat. I have had it for three years and just finished converting to WVO. It has always been gutless and has always gotten around 23-24 mpg. It appears to blow some oil out of the road vent tube and uses up some oil. It blows black smoke on the short hilly coast highway were I live. It is a heavy bed and I have two large built in boxes on the dump bed that are full of tools...... I am ready to make this puppy run good and get better MPG

[philip]

I am new here. I have an 82' 720 pickup sd22 engine. It has a dump bed w/duallys that appears to have been put on in LA, fresh off the boat. I have had it for three years and just finished converting to WVO. It has always been gutless and has always gotten around 23-24 mpg. It appears to blow some oil out of the road vent tube and uses up some oil. It blows black smoke on the short hilly coast highway were I live. SNIP

Veggie fuels result in reduced MPG. Since WVO users tout the freeness of their chosen fuel, I don't hear them placing the emphasis on MPG that we paying petro diesel users do.

Black smoke is too much fuel or it can be insufficient air. Refer to thread title: Smoke Setscrew. Periods of excessive fuel delivery raises combustion chamber temperatures (the opposit effect of rich mixtures in a gasoline engine). Excessive fuel delivery will contaminate the engine oil faster and in more severe cases, dilute the engine oil which in turn will increase your oil consumption and increase engine wear due to decreased oil viscosity. Lower quality or contaminated engine oil WILL result in more visible blowby out the road draft tube after a sustained climb.

I keep getting referenced to an egr valve that only has one flange. Mine has two flanges. Does anybody have a source for an 11/81 (1982?) sd22 vin# JN6SD02S2.....egr valve?

Here is your SD22 EGR valve in its native habitat. When you go to order one of these valves (and it's unlikely you need one), use the serial number on top of the valve. MANY parts counter monkeys just assume you are asking or mistaking your engine for the Z22 gasoline engine because their parts book do not list an SD22 engine. The EGR diaphragm does have a tiny leak built into it. But a few inches of contant vacuum will start to lift open the valve and then it will close again unless you continue to apply vacuum. Now ... how the EGR gets its vacuum signal is worthy of a new thread!

Is this really my problem if I have low power and bad fuel mileage?

Most likely not. In the SPECIAL context of this diesel having the Bosch inline pump, any manifold vacuum leak (which is what EGR is) will RAISE idle speed. It will NOT cause rough running. Also, if the vacuum amplifier (located under windshield wiper motor) or transducer and check valves (those two disc shaped things with vacuum hoses, mounted on a bracket blocking access to #4 glow plug) are malfuntioning, or the idle RPM set too high, the EGR will start cycling open/close at idle. This should not be. The engine will run fine without EGR operation. Simply remove the vacuum line.

There is a list of things that will reduce power in this diesel. An often overlooked item is the pneumatic governor diaphragm.

See thread title: "Pneumatic Governor Diaphragm"

Also, where are the marks for finding TDC when adjusting the valves?

See thread titles: Valve Adjustment and Injection Pump Timing

[Zoltan]

Just a little TLC can make a whole world of a difference. When I got my truck a couple of months ago, it had a greasy air filter, valves were not adjusted, it smoked like a barbeque, the oil filter looked like it had been there for years and the starter was held in by ONE LOOSE bolt. I was getting 25-28 mpg.

After replacing the filters, and adjusting the smoke screw and the valve lash, now I am getting 33-35 mpg in mixed city/hwy driving. Get good oil. First I used regular Shell 5W30 just to wash out the old gunk and the oil consumption was quite substantial. After a 1000 miles, I put 15w40 Valvoline Premium Blue and it seems like I have much less oil consumption and improved power.

[TheDieseliminator]

I am new here. I have an 82' 720 pickup sd22 engine. It has a dump bed w/duallys that appears to have been put on in LA, fresh off he boat. I have had it for three years and just finished converting to WVO.

Hi, and welcome to the site. Do you have any pictures of your 720 dually? I have always had the idea to build a 720 truck with a dual wheel rear axle and then drop in either an SD22 or preferably an SD25. Your truck sounds like a cool looking unit too. I'm sure the extra two rims in the rear are not a major factor in the fuel mileage you're seeing right now. You should have a 3.88 rear axle ratio, which is what the diesel trucks came with from the factory. The weight of the dump bed is probably a factor, but I would still think you could get at least 28-29 mpg with the truck. I'm sure after you replace a few of the parts stated above it will help you out with fuel mileage. Once again, sounds like you have a real nice truck and with a dump bed too. That is cool.

Salvy

[dually-dump]

Thanks for all the good replies, I am looking into all of them. The reason I was heading for a new EGR valve: I met this guy with a cherry 1980 Mercedes 5 cyl diesel (has been running 50/50 corn oil/diesel without any conversion) he put a vacuum gauge on my EGR valve and it did not hold a vacuum. Is it supposed to? My parts finding issues stem from the lack of a number on top the valve, looks like it rubbed off, I can almost read a part number on one photo sent to me but It sounds like the EGR valve isn't really needed so I will pursue other options and save the 70-80$. Also note, though I have converted the truck, I have only ran about 120 miles on veggie oil. I am focusing on getting the truck to run better and also setting up a good filtering station for the veggie oil. I will work on getting some pictures since this truck is really unique.

[philip]

Thanks for all the good replies, I am looking into all of them. The Reason I was heading for a new egr valve; I met this guy with a cherry 1980 Mercadies 5 cyl diesel ( has been running 50/50 corn oil/diesel without any conversion) he put a vaccum gauge on my egr valve and it did not hold a vaccum. Is it supposed to? My parts finding issues stem from the lack of a number on top the valve, looks like it rubbed off, I can almost read a part number on one photo sent to me but It sounds like The egr valve isnt really needed so I will persue other options and save the 70-80$. Also note, Though I have converted the truck, I have only ran about 120 miless on veggie oil. I am focusing on getting the truck to run better and also setting up a good filtering station for the veggie oil. I will work on getting some pictures since this truck is really unique.

THIS type of EGR valve has a small built-in bleed which I mentioned earlier. Were you to connect the vacuum pump to the egr. the EGR valve would open fully and immediately (normally).